Industrial vacuum loaders are used to load particulate or granular material from piles, bins, trucks, railroad cars, rail or truck spills, ship holds, or the like and often times are truck mounted with the truck having its own vacuum producing system which evacuates the air in the hopper or transport tank mounted on the truck body. Or such systems may be stationarily mounted in a fixed location in an industrial plant, or on railroad cars or other vehicles. Some such industrial vacuum loaders employ a large enclosed hopper into which the particulate or granular material such as iron ore, cement, bauxite, alumina or other products such as grain, ashes, or other products too numerous to mention, is drawn through pipe sections or a flexible loading hose attached to the hopper inlet and means are provided to unload the hopper in the same manner or by dumping or tilting. Low pressure for suction purposes is maintained in the hopper generally by means of a relatively large engine-driven positive displacement rotary blower which has its suction port connected to an air outlet port on the hopper and its pressure port connected to atmosphere. To prevent dust, fines or other extremely small air suspended particles in the material being loaded from being drawn from the hopper and through the blower for discharge to the atmosphere, dust filtration means are often connected between the air outlet port in the hopper and the suction port on the blower.
The efficiency of such systems depend on a number of factors, such as the amount of suction created by the blower, the restriction of the filtration system, the size of the pick-up hose and nozzle, etc. Especially when the system is truck-mounted these factors play an important part in reflecting the time element involved as the loading time directly affects the cost of the truck and driver and it becomes cost effective to get the truck loaded by an efficient method in the least time possible. The blower system, when truck-mounted, is limited in size for practical reasons and when its efficiency is further limited by the filtration system, additional efficiency is difficult to improve on.
This invention addresses this efficiency problem by providing a means to boost the flow of materials in the pick-up hose by means other than just the vacuum in the hopper, thus reducing the loading time substantially.